Magen—Darm

Abstract

When applying histochemical methods for the mucopolysaccharides, the glandulae labiales, palatinae and linguales were studied in human embryos and foetuses at different stages of development, till birth. — Our research has brought evidence that the mucopolysaccharides appear in the buds of the glands considered, during the process of canalisation of the solid epithelial columns, in which such substances are to be found in superficial sites of the still undifferentiated cells and in the spaces under formation between them. It is a matter of acid mucopolysaccharides which presumably are mixed with other neutral ones. — The product of the first typical mucous cells contains this same substance while mucocytes with an exclusively neutral secretion appear, as a rule, only in a further stage and are in small numbers, mixed with the others. In the earlier stages of development, the perceptible acid products are represented, at least predominantly by sialic acids; in the 5th month and in the following ones, the presence of sulphomucopolysaccharides is also demonstrated. — In the glandulae linguales the cells of the demilunes and the mucoserous ones of the tubules contain, from the 5th month onwards, neutral mucopolysaccharides and in a smaller extent, sialomucins. — From the present research it follows that already during intrauterine life the mucopolysaccharide production of the epithelia considered reaches the same histochemical characteristics which are met in the adult.